An air filter device or an air filter usually has a filter housing which has a housing pot with a pot bottom, a housing lid, a raw air inlet and a pure air outlet. The housing lid closes the housing pot axially opposite the pot bottom. Fresh air to be filtered is fed in via the raw air inlet. Filtered fresh air is discharged via the pure air outlet. Furthermore, an air filter usually comprises a filter element which has an annular filter body made from filter material, a first end plate which faces the housing lid on a first axial end side of the filter body, and a second end plate which faces the pot bottom on a second end side of the filter body. In the case of a filter body which is flowed through radially from the outside toward the inside, moreover, an inner frame can be provided which has an annular grid body which is arranged coaxially in the filter body. During operation of the air filter, a differential pressure which presses the filter body radially inward prevails on the filter body. Here, the filter body can be supported radially on the grid body of the inner frame. The grid body itself can be flowed through by the air flow and has no filter function in comparison with the filter body.
The filter element is arranged in the filter housing and, therein, usually separates a raw side which is connected fluidically to the raw air inlet from a pure side which is connected fluidically to the pure air outlet. In order to avoid leakages which bypass the filter body between the filter element and the filter housing, a seal is usually configured on one of the end plates, which seal bears against the filter housing.
WO 1998/36817 A1 has disclosed a filter element, in which a seal which is configured as a nonwoven seal is used on an end plate, which seal is welded to the end plate. A nonwoven seal consists of a nonwoven material, that is to say of fibers which are fixed to one another by way of felting. Here, plastic fibers are preferably used for nonwoven seals.
An air filter of the generic type is disclosed in US 2015/0 101 299 A1, wherein the second end plate has an annular first seal which bears sealingly against the housing pot, and wherein the second end plate has an annular second seal which bears sealingly against the inner frame.
Other air filters are known from US 2014/0 325 945 A1, EP 2 544 793 A1, and U.S. Pat. No. 6,086,763 A.